Mix graham cracker crumbs, melted butter, and sugar in a bowl until evenly combined. Press mixture firmly into bottom of 9-inch springform pan. Refrigerate while preparing filling.
Sprinkle gelatin over warm water and let bloom for 5 minutes, then stir until dissolved.
Beat cream cheese until smooth and fluffy. Gradually add powdered sugar and vanilla, mixing until well combined.
In separate bowl, whip heavy cream to stiff peaks.
Gently fold whipped cream into cream cheese mixture until just combined.
Divide mixture in half. To one half, add orange juice, orange zest, dissolved gelatin, and food coloring if desired.
Spread vanilla mixture over crust, then dollop orange mixture on top. Use knife to create swirl pattern.
Refrigerate for at least 4 hours or overnight until set.
Run knife around edges before removing from pan. Slice and serve chilled.